Abstract: The electromagnetic wave transmission with plane wave incidence through the rough surface of stratified medium is studied through expanding transmission field by plane wave and carrying out Fourier Transform to coordinates. This study method adopts small perturbation method according to Rayleigh hypothesis, and can avoid cumbersome derivation and proof. An exponential distribution rough surface is presented for describing the natural rough surface of stratified medium, and the formula of the transmission coefficient is derived with considering power spectrum density. Numerical results show that, the transmission coefficient grows with increasing dielectric constant real part of intermediate medium, and height fluctuation (root mean square) and correlation length of rough surface, while red